Back-up center back David Horst suffered a fully torn right Achilles tendon while playing with RSL’s USL franchise, Real Monarchs, on Tuesday in Herriman. The 32-year-old veteran MLS defender underwent surgery Thursday, but will miss the remainder of the 2018 MLS season.

In an Instagram post updating fans on his injury, Horst wrote: “The next few months will be difficult but I am so grateful to have the best support team around me.”

A post shared by David Horst (@davidhorst12) on Jun 29, 2018 at 7:33am PDT

Horst, who signed with RSL as a free agent in January 2017, has made 17 MLS appearances with the club in the last two years, including 11 starts. Prior to his season-ending injury, Horst also saw minutes with the Monarchs in 2018. Horst was originally drafted by RSL back in 2008 and has spent time with the Portland Timbers and Houston Dynamo in his 11-year MLS career.

The injury adds to a list that is lengthening at RSL.

Back-up goalkeeper Alex Horwath is out for the remainder of the season with a torn Achilles, while defenders Shawn Barry (knee) and Demar Phillips (ankle) have missed most of the 2018 campaign with respective injuries. Midfielder Luke Mulholland recently underwent back surgery. The RSL veteran has played in just one match this year while battling injuries.

The good news for RSL is that right back Tony Beltran is inching his way closer to returning to training. The 30-year-old has been out since suffering a knee injury last October that required two knee operations. Beltran is jogging during training sessions and is nearing a return to training with the team soon.